There is a vision tester that includes a main unit called Phoropter for disposing optical elements such as sphere lenses and cylinder lenses in front of the eye(s) of an examinee. The vision tester is arranged to present an optotype forward at a predetermined test distance to the examinee who views it through the optical elements disposed in front of the eye(s) for a subjective test (measurement) of refractive power and others of the examinee's eye(s).
In such vision tester, a visual field viewable through the optical elements disposed in a test window of the main unit is narrow. This would be likely to cause accommodation interference during a test. For this reason, there has been proposed an apparatus in which the test window and each optical element have larger diameters to widen the visual field in order to restrain the accommodation interference.
When each optical element has a larger diameter, a lens disk rotatably placed in the main unit to hold a plurality of such optical elements would also be increased in diameter, resulting in an increase in size of the main unit.